Resegmentation is an ancestral feature of the gnathostome vertebral skeleton

eLife

J Andrew Gillis¹  Katharine E Criswell² 

[1] Marine Biological Laboratory, Woods Hole, United States;Department of Zoology, University of Cambridge, Cambridge, United Kingdom;

关键词: somites;    vertebrae;    axial skeleton;    chondrichthyan;    segmentation;    evolution;   

DOI  :  10.7554/eLife.51696

来源: DOAJ

【 摘 要 】

The vertebral skeleton is a defining feature of vertebrate animals. However, the mode of vertebral segmentation varies considerably between major lineages. In tetrapods, adjacent somite halves recombine to form a single vertebra through the process of ‘resegmentation’. In teleost fishes, there is considerable mixing between cells of the anterior and posterior somite halves, without clear resegmentation. To determine whether resegmentation is a tetrapod novelty, or an ancestral feature of jawed vertebrates, we tested the relationship between somites and vertebrae in a cartilaginous fish, the skate (Leucoraja erinacea). Using cell lineage tracing, we show that skate trunk vertebrae arise through tetrapod-like resegmentation, with anterior and posterior halves of each vertebra deriving from adjacent somites. We further show that tail vertebrae also arise through resegmentation, though with a duplication of the number of vertebrae per body segment. These findings resolve axial resegmentation as an ancestral feature of the jawed vertebrate body plan.

【 授权许可】

Unknown